Cleanup TPU CI script error management (#14389)

dockers/tpu-tests/tpu_test_cases.jsonnet

@@ -21,6 +21,7 @@ local tputests = base.BaseTest {
   command: utils.scriptCommand(
     |||
       source ~/.bashrc
+      set -e
       conda activate lightning
       mkdir -p /home/runner/work/pytorch-lightning && cd /home/runner/work/pytorch-lightning
       git clone https://github.com/Lightning-AI/lightning.git
@@ -31,21 +32,18 @@ local tputests = base.BaseTest {
       git checkout {SHA}
       export PACKAGE_NAME=pytorch
       export FREEZE_REQUIREMENTS=1
-      export PL_STANDALONE_TESTS_BATCH_SIZE=1
       pip install -e .[test]
       echo $KUBE_GOOGLE_CLOUD_TPU_ENDPOINTS
       export XRT_TPU_CONFIG="tpu_worker;0;${KUBE_GOOGLE_CLOUD_TPU_ENDPOINTS:7}"
       export PL_RUN_TPU_TESTS=1
       cd tests/tests_pytorch
-      set -e
       coverage run --source=pytorch_lightning -m pytest -vv --durations=0 ./
       echo "\n||| Running standalone tests |||\n"
+      export PL_STANDALONE_TESTS_BATCH_SIZE=1
       bash run_standalone_tests.sh
-      test_exit_code=$?
       echo "\n||| END PYTEST LOGS |||\n"
       coverage xml
       cat coverage.xml | tr -d '\t'
-      test $test_exit_code -eq 0
     |||
   ),
 };